How Much Can I Borrow?

What does this calculator assume?

• Joint applicants combine incomes — typical lender practice for couples and close family.
• A 4.5× income multiple is used as the central estimate (lenders range from 4× to 5×+).
• Doesn't factor in your outgoings — credit cards, loans, childcare costs are deducted in real affordability checks.
• Doesn't assess your credit score, deposit source, or employment type.
• Doesn't haircut bonus or commission income — lenders often only use 50% of variable pay.

How do lenders actually calculate what I can borrow?

Most UK lenders cap borrowing at around 4.5× annual income — some go lower at 4×, some go higher at 5× or more for first-time buyers or specific products.

They then check whether the monthly payment fits your budget after committed outgoings, stress-tested at higher rates. So your actual maximum can be lower than a simple income-multiple result.

What's loan-to-value (LTV) and why does it matter?

LTV is the size of your mortgage as a percentage of the property price. A £200,000 mortgage on a £250,000 property is 80% LTV.

Lenders price mortgages in bands — typically 95%, 90%, 85%, 80%, 75%, and 60%. Lower LTV means better rates and more lender choice. Crossing a band (e.g. from 81% to 79%) can meaningfully cut your monthly payment.

Why might a lender offer less than this calculator shows?

Real lenders also check your outgoings, credit profile, deposit source, employment type, and stress-test affordability at higher rates. Bonus and commission may only count at 50%. Self-employed applicants are often assessed on the lower of recent years' profits. A poor credit footprint can knock down your multiple.

The calculator gives a ballpark; a broker or a real Agreement in Principle gives a real number.